01 - Preheat your oven to 350°F (175°C). Grease a 9x5-inch loaf pan and line it with parchment paper.
02 - In a large bowl, vigorously whisk together the mashed bananas, creamy peanut butter, melted and cooled unsalted butter, packed light brown sugar, room temperature large eggs, and vanilla extract until the mixture achieves a smooth consistency.
03 - In a separate bowl, thoroughly whisk together the all-purpose flour, baking soda, baking powder, salt, and ground cinnamon.
04 - Gently fold the dry ingredient mixture into the wet ingredient mixture until just combined. Exercise caution to avoid overmixing.
05 - If utilizing, carefully fold in the chopped roasted peanuts or chocolate chips.
06 - Pour the prepared batter into the greased and lined loaf pan, ensuring the top surface is smoothed evenly.
07 - Bake for 50–55 minutes. Test for doneness by inserting a toothpick into the center; it should emerge clean.
08 - Allow the bread to cool in the loaf pan for 10 minutes. Subsequently, carefully transfer it to a wire rack to cool completely before proceeding with slicing.